Faced following issue when trying to start database using pg_ctl:
FATAL: could not create lock file "/tmp/.s.PGSQL.5432.lock": Permission denied
Accidentally someone cleaned up /tmp and recreated it but without any write permissions to non-root user, if the non-root user write permissions are given to /tmp then it would start without any issues.
I was going thru some links and could find following (> 9+ years old thread):